1. Field of the Invention
The present invention relates generally to detecting and characterizing vibrating targets. More particularly, the present invention is directed to a radar system and method for detecting the vibration frequency of vibrating targets and for determining a characteristic vibration of vibrating targets, including an oscillation signature function (OSF).
2. Related Art
Most radar systems are used to detect non-periodic motion and/or distance. The modulation of radar return signals from periodic motion, such as oscillation and/or vibration, typically is viewed as a distortion on the radar return signals. This distortion can lead to degraded performance of the radar system.
Conventional radar systems which detect vibrating targets typically detect ghost images, or paired echoes, after imaging. The imaging of the radar return signal requires signal processing to obtain a narrowband frequency spectrum. This signal processing typically attenuates or eliminates the frequency components induced by vibration which degrades the radar system's capability to detect and characterize vibrating targets. Vibration information at frequencies exceeding the pulse rate frequency is lost through imaging.
What is needed is a system and method for detecting vibration frequency and characterizing a vibrating target directly from the stabilized phase history of a radar return signal.